JX4C数字摄影测量系统在高速公路测绘中的应用

从实际生产出发,记述了利用JX4C全数字摄影测量系统在高速公路测绘中的应用和体会.     

Seasonal and spatial characteristics of seawater and sediment at Youngil Bay, southeast coast of Korea

The seasonal geochemical characteristics of the seawater and sediments and the major factors causing heavy metal contamination were investigated at the Youngil bay and the Hyungsan river estuary in the Southeast Coast of Korea, where a world-scale steel-industry complex (Pohang iron and steel industrial complex, POSCO) is located. The seasonal and spatial distribution characteristics of temperature, dissolved oxygen (DO), pH, and nutrients of the seawater were studied at 45 fixed stations, especially focusing on the river mouth area. Sediments at 27 stations were examined during winter and summer to determine the major controlling factors for the distribution of metals, using correlation matrix and R-mode factor analyses, and to evaluate the pollution status, using the modified geoaccumulation (I(geo)(')) index. Temperatures for the effluent from the POSCO located at the Hyungsan river mouth were 2-3 degrees C higher compared to other sampling areas, due to the thermal discharge from the POSCO. The DO concentration of the surface water at the Pohang old port was as low as 2-4 mg/L. In spring, the DO value at the Hyungsan river mouth was higher than 12 mg/L, by the mass multiplication of phytoplanktons at the river mouth where seawater temperature and nutrients concentrations were relatively high, resulting in the pH value of higher than 8.3. The nitrogen to phosphorus (N/P) ratios at the river mouth were 20-150 times higher compared to other areas, implying that the nitrogen loading into this semi-enclosed bay is significantly higher than phosphorus and the major nitrogen sources are not only the domestic sewage from the city but the industrial wastewater from the POSCO and other steel factories nearby. The phosphorus concentrations at the Pohang old port were shown 3-10 times higher than those at other stations, due to the inflow of pollutants generated from the nearby ships anchoring and the release of phosphate from the bottom sediment. Results from the sediment analysis showed that the major controlling factors for the distribution pattern of each metal are grain size and organic carbon (C(org)) content. Based on the factor analysis, Al, Fe, Cr, Li, and Pb were shown strongly correlated with the mean grain size (Mz), whereas Cd, Cu, Zn, and Sn with the C(org) content. Results from the fractionation of the sedimentary metals into lattice and labile fractions to characterize the mobility of sediment metals showed that the mineral lattice fraction was high in the order of Al=K>Cr>Li>Sr>Fe, while the labile fraction, which might be released to the overlying water, was in the order of Pb>Zn>Cd>Cu>Ca>Sn. Evaluation of the sediment pollution status by applying (I(geo)(')) of 13 metals showed Cd, Cu, and Zn as high as 1-3 range at the old port. Even though the overall marine pollution mainly by the world-class steel industrial complex in this semi-enclosed bay area studied does not currently pose a serious threat, due to the seawater circulation and the large influx of river discharge, the countermeasures to implement the sediments concentrated with heavy metals, especially at the old port with no seawater circulation, are still warranted for this coastal water environment.     

Using SPIRAL (Single Pollen Isotope Ratio AnaLysis) to estimate C3- and C4-grass abundance in the paleorecord

C₃ and C₄ grasses differ greatly in their responses to environmental controls and influences on biogeochemical processes (e.g. water, carbon, and nutrient cycling). Difficulties in distinguishing between these two functional groups of grasses have hindered paleoecological studies of grass-dominated ecosystems. Stable carbon isotopic analysis of individual grains of grass pollen using a spooling-wire microcombustion device interfaced with an isotope-ratio mass spectrometer holds promise for improving C₃ and C₄ grass reconstructions. This technique, SPIRAL (Single Pollen Isotope Ratio AnaLysis), has only been evaluated using pollen of known C₃ and C₄ grasses. To test the ability of SPIRAL to reproduce the abundance of C₃ and C₄ grasses on the landscape, we measured δ¹³C values of > 1500 individual grains of grass pollen isolated from the surface sediments of ten lakes in areas that span a large gradient of C₃- and C₄-grass abundance, as determined from vegetation surveys. Results indicate a strong positive correlation between the δ¹³C-based estimates of % C₄-grass pollen and the abundance of C₄ grasses on the landscape. The % C₄-grass pollen slightly underestimates the actual abundance of C₄ grasses at sites with high proportions of C₄ grasses, which can be corrected using regression analysis. Comparison of the % C₄-grass pollen with C/N and δ¹³C measurements of bulk organic matter illustrates the distinct advantages of grass-pollen δ¹³C as a proxy for distinguishing C₃ and C₄ shifts within the grass family. Thus SPIRAL promises to advance our understanding of grassland ecology and evolution.     

标准卵磷脂氢过氧化物(PC-OOH)与亚油酸甲酯氢过氧化物(ML-OOH)制备

报道了用自由基引发剂（ＡＡＰＨ）引发氧化,反相高效液相色谱法分离卵磷脂（Ｐｈｏｓ－ｐｈａｔｉｄｙｌｃｈｏｌｉｎｅ,ＰＣ）及其氢过氧化物（ＰＣ－ＯＯＨ）,获得纯品ＰＣ－ＯＯＨ,以及５０℃自动氧化后,用硅胶柱层析分离亚油酸甲酯（ＭｅｔｈｙｌＬｉｎｏｌｅａｔｅ,ＭＬ）及其氢过氧化物（ＭＬ－ＯＯＨ）,而获得标准ＭＬ－ＯＯＨ的方法。     

煤系高岭土合成4A沸石试验研究

本试验所用原料为大同怀仁和徐州夹河煤系高岭土,这两种原料的ＳｉＯ２和Ａｌ２Ｏ３分子比均接近于２,其成分能满足合成４Ａ沸石的要求。本试验首先进行了原料的焙烧活化及漂白的试验研究,解决了原料的白度问题。分析探讨了合成４Ａ沸石过程中成分、碱度、温度、时间及搅拌等对合成试验的影响,并通过对比试验获得了最佳合成条件,得到了合格的４Ａ沸石产品。     

浅谈如何升级TTY4气象报文填图系统

针对我局TTY4气象报文自动填图系统PC/XT微机硬件老化,运行极不稳定,影响正常业务工作,在升级计算硬件与操作系统中所遇到的问题和解决办法上作了简要的介绍.     

Seabirds in the North Sea Demobilized and Killed by Polyisobutylene (C4H8)n (PIB)

This paper reports on a mass stranding of seabirds in the North Sea in December 1998. Hundreds of birds were washed ashore alive in Zeeland (SW Netherlands), covered in a whitish, sticky substance, and were transported to a rehabilitation centre. About 10 days later, more (dead) casualties washed ashore further to the north on Texel and along the mainland coast, again covered in a glue-like substance. Common guillemots Uria aalge, northern fulmars Fulmarus glacialis and common scoters Melanitta nigra were the most numerous birds affected in this incident. Both strandings were temporarily (10 days) and geographically separated (ca. 120 km apart), but were apparently caused by a single source of pollution. The meteorology at the time was consistent with the course of a single incident. At least 1100 seabirds were affected by this substance, soon identified as polyisobutylene (C₄H₈)_n. PIB is known as a non-toxic, non-aggressive substance. Volunteers cleaning the birds in the rehabilitation centre reported serious discomfort and dizziness and the soft parts of the PIB-affected birds found dead (bill, eye, throat, feet, webs) appeared to dissolve in a few days time. Both effects cannot be attributed to PIB, and are therefore unexplained. Although the dumping of PIB in the marine environment is not explicitly prohibited under MARPOL, the effects on wildlife observed are enough to plead for counter-measures.     

象山港潮波响应和变形研究 Ⅲ.潮滩位置和平流效应对M4分潮的作用

通过半封闭矩形理想海湾的潮波运动数值模拟,分析了潮滩及平流效应对M₄分潮的生成和增长的影响.结果说明潮滩的作用不但依赖本身的规模和湾内潮波非线性的强弱,而且与潮滩在湾内所处位置关系很大.在存在M₄分潮共振的海湾中,平流效应可以抑制共振对M₄分潮的放大作用.     

Optical spectroscopy of GX 339−4 during the high–soft and low–hard states – I

We carried out spectroscopic observations of the candidate black hole binary GX 339−4 during its low–hard and high–soft X-ray states. We have found that the spectrum is dominated by emission lines of neutral elements with asymmetric, round-topped profiles in the low–hard state. In the high–soft state, however, the emission lines from both neutral and ionized elements have unambiguously resolved double-peaked profiles. The detection of double-peaked emission lines in the high–soft state, with a larger peak separation for higher ionization lines, indicates the presence of an irradiatively heated accretion disc. The round-topped lines in the low–hard state are probably caused by a dense matter outflow from an inflated non-Keplerian accretion disc. Our data do not show velocity modulations of the line centres caused by the orbital motion of the compact object, neither do the line basewidths show substantial variations in each observational epoch. There are no detectable absorption lines from the companion star. All these features are consistent with those of a system with a low-mass companion star and low orbital inclination.